This is not the first strip in which CB's empathic relationship with his father comes out. It only rarely comes up in the strip, but Charlie Brown greatly loves his father, and it's rather heartwarming, and I don't think in a saccharine way since it's often used as a subtext for a joke, when his expressions of affection come up.
Charles Schulz's father was a barber, like Charlie Brown's, who struggled to support his family through the Great Depression. After Charles Schulz's mother died shortly before he entered military service, he had to rely on his father for a period after he returned home. The two would pore over the comics pages of the newspapers each Sunday; they subscribed to two St. Paul papers, and Sparky would also pick up two Minneapolis papers from a drug store so they had four comics sections to go through.
The death of Schulz's father was possibly the reason Charlie Brown's father stopped figuring in the strips. Schulz seemed to take things from his life and give them a place in the strip. This theory would also explain those characters who would be introduced and even hang around for a long while, even becoming major players, before vanishing never to be seen again. These characters may have been based upon people Schulz knew, and when they left his circle of experience, the inspiration for writing them would dry up.
